Left Ventricular Assist Devices: A Primer For the General Cardiologist

Figure 1. Trends in the rate of 1‐year survival across clinical study groups over time. A and B, Display the 1‐year survival rates for patients enrolled in large studies of left ventricular assist devices. A, Patients implanted as bridge‐to‐transplant or bridge‐to‐transplant‐candidacy (both represented as open circles). B, Patients implanted as destination therapy (solid circles). Data are shown according to the respective start dates of each study. Each circle is color coded for each type of implanted device with purple for HeartMate XVE, maroon for HeartMate II, green for HeartWare, and blue for HeartMate 3. The study is labeled on the figure and data are listed in Table S1. The area of each circle represents the sample size in each group (reference sizes are shown in the key). BTC indicates bridge to candidacy; BTT, bridge to transplant; BTTC, bridge to transplant candidacy; DT, destination therapy; and VAD, ventricular assist device.

Figure 2. Components of contemporary left ventricular assist devices. This figure summarizes key internal and external components of contemporary left ventricular assist devices. (1) Blood flows from the left ventricle to the inflow cannula (not shown but inserted into the left ventricular apex) through the pump and into the outflow graft to the aorta; (2) the driveline extends from the pump and out through the abdominal wall to the (3) external controller; (4) the main energy source for the pump is external batteries or an AC power source (not shown). AC indicates alternating Current; CV‐LVADs, continuous flow left ventricular assist device; HMII, HeartMate II; HM3, HeartMate 3; and rpm, rotations per minute.

Figure 3. Ineffective blood flow in patients with a left ventricular assist device and aortic insufficiency. A, Displays the ineffective (circular) flow of blood in patients with a left ventricular assist device and aortic insufficiency. Blood is flowing primarily from the left ventricular apex to the pump, to the aorta, back through the incompetent aortic valve, and back to the left ventricular apex and pump without flowing to the periphery. B, Displays the normal flow of blood in patients with a left ventricular assist device and no aortic insufficiency. LA indicates left atrium; LV, left ventricle; LVAD, left ventricular assist device; RA, right atrium; and RV, right ventricle.

Figure 4. Method to obtain blood pressure in patients with left ventricular assist devices. BP indicates blood pressure; LVAD, left ventricular assist device; and MAP, mean arterial pressure.